First established by Cistercian monks in the 12th century, Kirkstall Forge is claimed to be the longest continually used industrial site in Britain. Following its closure in 2002, the site was acquired by CEG and is undergoing a £400m regeneration to provide ca 1,000 new homes, retail and leisure facilities, and a railway station linking the riverside to the city centre.
Tetra Tech’s full scope of work covers the infrastructure design, geotechnical design, earthworks design and specification, ground and groundwater contamination, remediation design and specification, and more.
Design quality and innovation
Infrastructure and connectivity were strategically important to the client and local authorities. To support this, our approach called for infrastructure to be implemented in phases, adapting to commercial, retail, or residential use without constraining other development. From ahighway and bridge linking to a new railway station, to a reinforced soil wall and the design of utilities associated with initial phases of redevelopment, our work has been enormously expansive.
The innovative design developed from this addresses the complexities of the steeply sloping site, bisected by the River Aire, through creative adaptation of standard solutions to meet specific challenges. Replacing 210m of the northern river bank and 125m of the southern with reinforced earth retaining walls has raised them by five metres to create suitable highway gradients and support the 30m span bridge, central to the connectivity of the site.
This new bridge is founded on concrete bank seats built directly on the reinforced soil structures and is the first in the UK to use this construction method to span a river. At 18m wide, it supports three traffic lanes and wider-than-normal footways designed to encourage pedestrian use and support the public realm strategy.
In another first for the UK, a cantilevered pedestrian platform is founded directly in the reinforced embankment to overhang the river and further enhance the public realm.
Sustainability
A number of design decisions, including the remediation criteria and the earthworks specification, have resulted in the on-site retention of excavated materials excavated. Most were processed and sustainably re-used during the enabling works while limited quantities were held for future phases of development.
Collaboration
Complex stakeholder involvement and buy-in was key to the success of this project. During construction our civil and structural engineers acted as lead consultant coordinating all multi-discipline engineering matters and reporting directly to the client’s representative.
Impact
The completed infrastructure and enabling works have already had a significant impact on the regeneration of the area, allowing benefits to be realised prior to development of buildings on site and creating a robust framework for further transformation.
Resonating with the UK government’s plans to improve economic growth and connectivity across the north of England, Kirkstall Forge will improve the local environment and create around 2,400 new jobs, boosting the local economy by more than £5m per year.
